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In this paper, we study the proximal incremental aggregated gradient (PIAG) method for minimizing the sum of smooth component functions and a nonsmooth function, both of which are allowed to be nonconvex. We show the linear convergence rate result under the metric subregularity and proper separation condition. Our method is developed based on a special auxiliary Lyapunov function sequence, and we also show that this auxiliary sequence is Q-linearly convergent. Using this result, we obtain an explicit computable stepsize threshold to guarantee that the objective value and iterative sequences are R-linearly convergent. Preliminary computational experience is also reported. [ABSTRACT FROM AUTHOR]

This paper investigated the microstructure and mechanical properties of Q235/304 stainless steel clad plate welding seam produced by hybrid welding of tungsten inert gas welding (TIG) and metal active gas arc welding (MAG). The results showed that the dual phases containing ferrite and austenite appeared in the stainless steel covering welding (SSCW), while the partial martensite phases appeared in the carbon steel backing welding (CSBW), which is attributed to the dilution behavior of Ni and Cr elements from stainless steel to the Q235 steel results into the movement of the CCT curve to the right side and the decrease of critical martensite formation cooling rate. The CSBW possesses the highest microhardness value in the weld metal due to the existence of the martensite zone. The impact tests were carried out and the results showed that the Charpy absorbed energy of weldments (81 J) is almost equal to that of base clad plate (83 J). The SSCW layer possesses the ductile fracture characteristics accompanying many dimples. However, in the CSBW layer, some cleavage fracture characteristics are presented in the radiation zone while many dimples are located in the fibrous zone, revealing a complex combination of brittle and ductile fracture behavior, which is due to the existence of martensite zone, different stress states and crack propagation velocity. Hybrid (TIG, MAG) welding is suitable for welding stainless steel clad plate; The martensite formation in CSBW is related to dilution and diffusion of Cr and Ni; Partial martensite transformation can strengthen and toughen the welding seam. [ABSTRACT FROM AUTHOR]

1. This experiment was conducted to evaluate the effects of dietary supplementation of resveratrol on laying performance, egg quality, egg yolk cholesterol and antioxidant enzyme activities of laying hens. 2. A total of 360 Beijing PINK-1 laying hens (60 weeks old) were randomly distributed among five dietary treatments, each of which included 6 replicates of 12 hens. Dietary treatments were basal diet supplemented with 0 (control), 0.5, 1.0, 2.0 and 4.0 g/kg diet resveratrol. The study lasted for 9 weeks including 1 week of adaptation and 8 weeks of the main experimental period. 3. The results indicated that dietary resveratrol significantly improved feed conversion ratios during 5–8 weeks and 1–8 weeks of the trial. Increasing dietary concentrations of the resveratrol linearly improved Haugh unit and albumen height of eggs. 4. The content of total cholesterol (TC), total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C) in serum and cholesterol in yolk was significantly decreased by dietary resveratrol, and there were significant linear correlations between these indexes and resveratrol supplemental levels. 5. Dietary resveratrol supplementation significantly improved serum Glutathione peroxidase (GSH-Px) enzyme activity and decreased serum malondialdehyde (MDA) content in groups with 2.0 and 4.0 g/kg resveratrol as compared to the control, respectively. However, supplementation of resveratrol did not affect the activity of serum superoxide dismutase (SOD). 6. It is concluded that resveratrol supplementation has a positive effect on performance, lipid-related traits and antioxidant activity of laying hens. [ABSTRACT FROM PUBLISHER]

The well-developed continental shale sequences in the Western Sichuan Depression are characterised by extremely low porosity and permeability, complex lithologies and strong lateral facies changes. The overall lack of proper characterisation of the shale properties has restricted gas exploration and development in the region. In this study, shales from the fifth member of the Xujiahe Formation of the Upper Triassic (T3x5) are comprehensively characterised in terms of their organic geochemistry, mineral composition, microscopic pore structure and gas content. In addition, the influence of various geological factors on the adsorbed gas content is investigated. We proposed a new model for predicting the adsorption gas content of continental shale. The T3x5shale sequence is found to be rich in organic matter but with variable mineral compositions, pore types and reservoir physical properties. The porosity and permeability of shales are better than those of siltstones and fine sandstones interbedded with the shale under an overall densification background. Mesopores (2–50 nm) are common in the shale sequence, followed by micropores and then macropores. The gas-adsorption capacity of organic-rich shales increases with increasing TOC and clay-mineral contents, maturity and pressure, but decreases with increasing quartz content, carbonate minerals and temperature. The gas-adsorption capacity can thus be expressed as a function of organic matter, clay-mineral content, temperature and pressure. The calculated results are in good agreement with the experiment results and indicate that adsorption gas in the studied shales accounts for 78.9% of the total gas content. [ABSTRACT FROM PUBLISHER]

In maritime simulators there are problems of discontinuity and saltation on radar simulation images caused by the limited range of radar simulation data generated from a single electronic chart. Furthermore, this kind of radar simulation is overlapping, discontinuous and redundant, and thus could lead to simulation error and training interruption. To address this problem, a method is presented to generate a wide range of radar simulation data based on a multi-scale chart data. The method uses automatic splicing on same-scale maps and variable-scale visualisation splicing on multi-scale maps. In this paper, the S-57 standard electronic navigational charts are filtered from the S-57 database and then radar simulation data are generated based on charts of different scales. From clipping, sorting, deletion, combination and matching, a wide range of continuous radar simulation data are generated. Taking the waters around Ningbo Port, China as an example, 27 chart sections are filtered out from S-57 database, with a longitude range from 121°33' to 122°56.8' and a latitude range from 29°3' to 30°21.8'. The wide-range and continuous radar simulation data are generated for a maritime simulator. The results validate this method as being highly accurate and able to meet the practical needs of maritime simulation. [ABSTRACT FROM PUBLISHER]

High Cr ferritic heat-resistant steels have been the important structural materials for elevated temperature application in the advanced power plants. Owing to the severe difficulties encountered by energy shortage and environment pollution, it is imperative to improve the serving temperature up to 650° which would largely elevate the thermal efficiency of generating station. In this paper, the phase transformation behaviours, strengthening mechanism and the formation the precipitates of high Cr ferritic steels were summarised. Based on these, the modified high Cr ferritic steel for 650 °C condition was developed by our group. The tensile and creep tests indicate that the modified steel has the outstanding mechanical properties, suggesting it may be the candidate materials in advanced power plants for 650 °C grade. Furthermore, developments of the modified high Cr ferritic steels will be presented and discussed in views of microstructural control, alloy design, phase transformation behaviours and high-temperature performance. [ABSTRACT FROM AUTHOR]

Amagnetic mesoporous silicon (MMS) composite with magnetic particles as the core andmesoporous as the shell was prepared. The MMS composite was characterised by means of transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption. The MMS composite with the pore-size of 2 and 200 nm in diameter had a good application prospect in the magnetic-induction hyperthermia and drug delivery. The composite function of magnetic-induction hyperthermia was measured by a high-frequency-induction heating machine with the frequency 608 kHz and the field amplitude 6.4 kA m-1.The magnetic mesoporous composite took about 7 min to heat up 45°Cwith the average heating rate of 2.25°C min-1.The function of loading doxorubicin (DOX) hydrochloride was measured at 488 nm on a UV-Vis spectrophotometry, and the loading efficiency with 20.1% was achieved for the DOX hydrochloride being possibly loaded into the mesoporous. This result putMMSa way of the synchronised therapy of hyperthermia and magnetic target drug delivery. [ABSTRACT FROM AUTHOR]

The transformation characteristics of low-carbon high strength low alloy steel for various cooling rates were systematically investigated by means of dilatometric measurements and microstructure observations. According to the results, it is recognised that the increase of the cooling rate could lead to microstructure evolution from a mixture of polygonal ferrite, acicular ferrite and bainite ferrite to the dual phase of acicular ferrite and bainite ferrite. The kinetics mechanism of the phase transformation was further studied by a modified analytical phase transformation model, which involves site saturation, diffusion/interface-controlled growth, impingement correction for randomly distributed growing particles. It is demonstrated that diffusion-controlled polygonal ferrite and acicular ferrite phase transformation precedes the interface-controlled bainite ferrite phase transformation. For the diffusion-controlled growth, the transformation is slowed down with the increase of the cooling rate, which prevents the diffusion process to some degree and increases the diffusion activation energy QD. For the interface-controlled growth, the interface migration activation energy shows a declining trend with the increase of cooling rate, thus promoting the transformation. [ABSTRACT FROM AUTHOR]

For high Cr ferritic heat-resistant steels, dispersion hardening has played a vital role in improving creep strength at high temperatures. In this paper, the various types of precipitates in high Cr ferritic steels are reviewed, concerning M3C, M23C6, MX, M2 X, Laves phase and Z phase. The evolution of these precipitates is a complicated process, since the dissolution of one type of precipitate may be overlapped with the precipitation of another type or other types. The composition of some precipitations varies towards the equilibrium composition under certain conditions, which is relevant to the solubility and diffusivity of the alloying element, while the composition of some other precipitates changes slightly. For the precipitates in high Cr ferritic steels, the preferred nucleation sites involve prior austenite grain boundaries, lath boundaries, dislocations and the interfaces between the precipitates and the matrix. [ABSTRACT FROM AUTHOR]

Semimetallic friction composites with and without bionic non-smooth structure were prepared and then tested to evaluate their friction wear properties. The variation of friction coefficients of the friction composites is relatively steady. The friction coefficients of the testing sample with bionic non-smooth structure of NO.2, NO.3 and NO.4 were lower than that without bionic structure. The wear rate of the friction composites greatly increased under a temperature increasing procedure, especially when the temperature exceeds 250°C. The wear rates of the testing samples of NO.2 and NO.3 are the lowest compared with others (NO.1 and NO.4) at various temperatures except for 100°C. The worn morphology of the friction composites after the friction testes was observed using the scanning electron microscope for analysing the worn characteristics. The results showed that the bionic structure of testing samples of NO.2 and NO.3 had better wear resistance and provide stable friction coefficient compared with others. [ABSTRACT FROM AUTHOR]

A detailed investigation was carried out on the effect of austenisation temperature on the phase transformation in X65 microalloyed pipeline steel during continuous cooling at a rate of 200°C min−1 by means of high resolution dilatometric measurement and microstructure observation. The results showed that with austenisation temperature increasing in the range of 850–1000°C, phase transformation temperature range shifts to lower temperatures and the formation of acicular ferrite phase is promoted. Furthermore, the increase in austenisation temperature results in refined grains after continuous cooling to room temperature, associating with the appearance of acicular ferrite structure in steel. The present investigation is helpful to optimise the parameters of rolling or heat treatment technology in industrial production of X65 steel. [ABSTRACT FROM AUTHOR]

Aiming to optimise the thermal treatment technology of WB36 heat resistant steel, the characteristics of phase transformations during continuous cooling at 5–2000°C min−1 were investigated by means of microstructure observation and dilatometric measurements. The continuous cooling transformation diagram of WB36 heat resistant steel was obtained, as well as the fractions of different transformation products obtained under various cooling conditions. The results showed that the transformation products in continuously cooled WB36 heat resistant steel involve polygonal ferrite, pearlite, granular bainite and lath martensite, with increasing cooling rates from 5 to 2000°C min−1. Owing to the Mo addition to the steel, the super cooled austenite in WB36 heat resistant steel was stabilised significantly, and granular bainite can be obtained in a wide range of cooling rate. However, the substructures of granular bainite vary significantly with the increase in cooling rate, including matrix morphology and the distribution of M/A islands in the matrix. [ABSTRACT FROM AUTHOR]

The thermal dilation behaviours of modified high Cr ferritic heat resistant steel quenched at different temperatures were employed to investigate the kinetics of martensite transformation. The martensite fraction and formation rate were obtained as a function of temperature. A model considering 'spread' martensites was introduced to explore the influence of quenching temperatures on martensite transformation. Both onset and offset temperatures of martensite formation decrease with the increase in quenching temperatures, and the reaction rate increases rapidly at the beginning of transformation and reaches a peak when a small quantity of martensite forms. The fitted data based on the proposed phase transformation model indicated that the width/length ratio of martensite laths decreases with the increase in quenching temperatures. [ABSTRACT FROM AUTHOR]

This paper presents a method to extract buildings in monocular urban aerial images without prior knowledge of illumination. With a building concept model to interpret buildings at different levels and scales, building extraction is carried out in two stages: sunshine parts extraction and self-shadow parts extraction. Based on region-oriented radiometric features, images are first simplified and segmented into three parts: sunshine parts of high objects, shadow regions and sunshine ground. To verify initial segmentations, a method of estimating the direction of shadow cast was proposed by a shadow context model. Building extractions were then refined by context and a modified partial snake model with the aid of the shadow cast direction, thus sharply reducing the iteration complexity and the influence of illumination. An innovative method for extracting self-shadows on gable roofs is also discussed. [ABSTRACT FROM AUTHOR]

The problem of robust guaranteed cost control for a class of time-varying uncertain discrete delay systems is studied. The guaranteed cost control law is implemented by using a dynamic output feedback compensator. The proposed methods are given in terms of linear matrix inequalities (LMIs). A numerical example is given to demonstrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

The phenomena of natural-convection boiling and critical heat flux on the outer surface of a heated hemispherical vessel surrounded by a thermal insulation structure were investigated experimentally. The objectives were to observe the behavior of the boiling-induced two-phase motion in the annular channel formed between the hemispherical vessel and the insulation structure and to determine the flow effect on the natural-convection boiling process on the downward-facing hemispherical surface. High-speed photographic records revealed the presence of violent cyclic ejection of the vapor masses generated by boiling on the vessel outer surface, which resulted in a buoyancy-driven, upward, co-current two-phase flow through the channel. When boiling was taking place at high heat flux levels, the flow through the minimum gap of the channel was found to be highly unsteady and chaotic. Measurements of the local boiling heat fluxes and the local wall superheats were made which showed a significant spatial variation of the nucleate boiling heat transfer. Owing to the effect of the unsteady and chaotic two-phase motion, the local critical heat flux had the lowest value near the minimum gap. [ABSTRACT FROM AUTHOR]

High-quality amorphous silicon-nitrogen alloys (a-SiN x have been deposited at room temperature by a sputtering-type electron cyclotron resonance (ECR) plasma. A detailed analysis of the properties of a-SiN x films in terms of their composition, microstructure and dielectric characteristics was performed using Xray photoelectron spectroscopy, infrared (IR) spectroscopy and ramp currentvoltage measurement techniques. Their characteristics were correlated with the N2 gas flow rate (NGFR) in the ECR plasma formation. The dependence of solidstate [N]/[Si] ratios in the films on the NGFR indicated that the film composition changed from non-stoichiometry to stoichiometry as the NGFR increased from 0.5 to 1 sccm. The dependence of the IR spectra on the NGFR indicated that silicon nitride network was well ordered for an NGFR of 1 sccm, in which the dielectric breakdown-field was over 4 MV cm 1. However, when the NGFR was over 1 sccm, significant N N triple bonds (gaseous N2 molecule) were formed and were trapped inside the films. These N2 molecules formed many voids and defects; and enhanced disorder in the network. This is well correlated by chemical etch and IR results. The dependence of dielectric properties of a-SiN x films on the NGFR demonstrated that these voids and defects lead to a decrease in average dielectric breakdown field and an obvious increase in the distribution of the low breakdown field. [ABSTRACT FROM AUTHOR]